Clinical Topics & News

VHA Practice Guideline Recommendations for Diffuse Gliomas

Fed Pract. 2018 August;35(5):S28-S35

References

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3. Ostrom QT, Gittleman H, Liao P, et al. CBTRUS statistical report: primary brain and other central nervous system tumors diagnosed in the United States in 2010-2014. Neuro Oncol. 2017;19(suppl 5):v1-v88.

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5. Cairncross JG, Ueki K, Zlatescu MC, et al. Specific genetic predictors of chemotherapeutic response and survival in patients with anaplastic oligodendrogliomas. J Natl Cancer Inst. 1998;90(19):1473-1479.

6. van den Bent MJ, Erdem-Eraslan L, Idbaih A, et al. MGMT-STP27 methylation status as predictive marker for response to PCV in anaplastic oligodendrogliomas and oligoastrocytomas. A report from EORTC study 26951. Clin Cancer Res. 2013;19(19):5513-5522.

7. Stupp R, Hegi ME, Mason WP, et al; European Organisation for Research and Treatment of Cancer Brain Tumour and Radiation Oncology Groups; National Cancer Institute of Canada Clinical Trials Group. Effects of radiotherapy with concomitant and adjuvant temozolomide versus radiotherapy alone on survival in glioblastoma in a randomised phase III study: 5-year analysis of the EORTC-NCIC trial. Lancet Oncol. 2009;10(5):459-466.

8. Malmstrom A, Gronberg BH, Marosi C, et al. Temozolomide versus standard 6-week radiotherapy versus hypofractionated radiotherapy in patients older than 60 years with glioblastoma: the Nordic randomised, phase 3 trial. Lancet Oncol. 2012;13(9):916-926.

9. van den Bent MJ, Kros JM. Predictive and prognostic markers in neuro-oncology. J Neuropathol Exp Neurol. 2007;66(12):1074-1081.

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14. Wick W, Platten M, Meisner C, et al; NOA-08 Study Group of Neuro-oncology Working Group (NOA) of German Cancer Society. Temozolomide chemotherapy alone versus radiotherapy alone for malignant astrocytoma in the elderly: the NOA-08 randomised, phase 3 trial. Lancet Oncol. 2012;13(7):707-715.

15. Horbinski C, Kofler J, Kelly LM, Murdoch GH, Nikiforova MN. Diagnostic use of IDH1/2 mutation analysis in routine clinical testing of formalin-fixed, paraffin-embedded glioma tissues. J Neuropathol Exp Neurol. 2009;68(12):1319-1325.

16. Camelo-Piragua S, Jansen M, Ganguly A, Kim JC, Louis DN, Nutt CL. Mutant IDH1-specific immunohistochemistry distinguishes diffuse astrocytoma from astrocytosis. Acta Neuropathol. 2010;119(4):509-511.

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Case Presentations

Case 1. A veteran of the Gulf War presented with a 3-month history of possible narcoleptic events associated with a motor vehicle accident. Magnetic resonance imaging (MRI) revealed a large left frontal mass lesion with minimal surrounding edema without appreciable contrast enhancement (Figures 1A, 1B, and 1C).

The patient subsequently underwent a stereotactic biopsy that revealed slightly hypercellular brain tissue composed of cells with round to ovoid hyperchromatic nuclei, which infiltrated the overlying cortex (Figure 1D).

Neither mitotic figures nor endothelial proliferation were identified. Immunohistochemical stains revealed a lack of R132H mutant IDH1 protein expression, a loss of nuclear staining for ATRX protein within a substantial number of cells, and a clonal pattern of p53 protein overexpression (Figures 1E, 1F, and 1G). The lesion demonstrated diffuse glial fibrillary acidic protein (GFAP) immunoreactivity and a low proliferation index (as determined by Ki-67 staining; estimated at less than 5%) (Figures 1H and 1I).

Based upon these results, an initial morphologic diagnosis of diffuse glioma was issued, and tissue was subjected to a variety of nucleic acid-based tests. While fluorescence in situ hybridization (FISH) studies were negative for 1p/19q codeletion, pyrosequencing analysis revealed the presence of a c.394C>T (R132C) mutation of the IDH1 gene (Figure 1J). The University of Pittsburgh Medical Center’s GlioSeq targeted next-generation sequence (NGS) analysis confirmed the presence of the c.394C > T mutation in IDH1 gene.⁴ Based upon this additional information, a final integrated morphologic and molecular diagnosis of diffuse astrocytoma, IDH-mutant was rendered.

Case 2. A Vietnam War veteran presented with a 6-week history of new onset falls with associated left lower extremity weakness. A MRI revealed a right frontoparietal mass lesion with surrounding edema without appreciable contrast enhancement (Figures 2A, 2B, and 2C).

The patient subsequently underwent a diagnostic craniotomy that revealed a variably cellular neoplasm composed of cells with round to ovoid nuclei, which infiltrated the overlying cortex and contained rare psammoma bodies. The neoplasm contained multiple nodular foci of hypercellularity, focally brisk mitotic activity, and focal endothelial proliferation, although areas of necrosis were not identified.

Immunohistochemical stains revealed R132H mutant IDH1 protein expression, retention of nuclear staining for ATRX protein, the lack of a clonal pattern of p53 protein overexpression, diffuse GFAP immunoreactivity, and a proliferation index (as determined by Ki-67 staining) focally approaching 20% (Figures 2E, 2F, 2G, 2H and 2I).

Based upon these results, an initial morphologic diagnosis of diffuse (high grade) glioma was issued, and tissue was subjected to a variety of nucleic acid-based tests. The FISH studies were positive for 1p/19q codeletion, and pyrosequencing analysis confirmed the immunohistochemical findings of a c.395G>A (R132H) mutation of the IDH1 gene (Figure 2J). GlioSeq targeted NGS analysis confirmed the presence of the c.395G>A mutation in the IDH1 gene, a mutation in the telomerase reverse transcriptase (TERT) promoter, and possible decreased copy number of the CIC (chromosome 1p) and FUBP1 (chromosome 19q) genes.

A final integrated morphologic and molecular diagnosis of anaplastic oligodendroglioma, IDH-mutant and 1p/19q-codeleted was rendered based on the additional information. With this final diagnosis, methylation analysis of the MGMT gene promoter, which was performed for prognostic and predictive purposes, was identified in this case.^5,6

Case 3. A veteran of the Vietnam War presented with a new onset seizure. A MRI revealed a focally contrast-enhancing mass with surrounding edema within the left frontal lobe (Figures 3A, 3B, and 3C).

The patient subsequently underwent a diagnostic craniotomy that revealed a poorly demarked mucoid lesion. Intraoperative cytology revealed a noncohesive, process poor neoplasm predominantly composed of cells with small-to-medium round to slightly irregular nuclei in the background of thin vessels. Rare mitotic figures as well as scattered cells with fibrillary processes and larger hyperchromatic nuclei with irregular nuclear membranes were identified.

Hematoxylin and eosin (H&E) stained sections following formalin fixation and paraffin embedding demonstrated similar findings (Figure 3D), and while mitotic figures were readily identified, areas of necrosis were not identified and endothelial proliferation was not a prominent feature. Immunohistochemical stains revealed no evidence of R132H mutant IDH1 protein expression, retention of nuclear staining for ATRX protein, a clonal pattern of p53 protein overexpression, patchy GFAP immunoreactivity, and a proliferation index (as determined by Ki-67 staining) focally approaching 50% (Figures 3E, 3F, 3G, 3H, and 3I).

Based upon these results, an initial morphologic diagnosis of diffuse (high grade) glioma was issued, and the tissue was subjected to a variety of nucleic acid-based tests. The FISH studies were negative for EGFR gene amplification and 1p/19q codeletion, although a gain of the long arm of chromosome 1 was detected. Pyrosequencing analysis for mutations in codon 132 of the IDH1 gene revealed no mutations (Figure 3J). GlioSeq targeted NGS analysis identified mutations within the NF1, TP53, and PIK3CA genes without evidence of mutations in the IDH1, IDH2, ATRX, H3F3A, or EGFR genes or the TERT promoter. Based upon this additional information, a final integrated morphologic and molecular diagnosis of GBM, IDH wild-type was issued. The MGMT gene promoter was negative for methylation, a finding that has prognostic and predictive impact with regard to treatment with temazolamide.^7-9